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Smartphone Game Shows Old Folks Unwilling To Gamble To Win; Are Dwindling Pleasure Chemicals In The Brain To Blame?

People love games: they’re a fun way to pass the time. University College London scientists took advantage of this aspect of human nature to learn what happens at the intersection of risk-taking and growing old. Creating a special smartphone game to use in their experiments, Dr. Robb Rutledge and his colleagues discovered older people were less likely than younger people to choose risky gambles when it came to trying to win points. Yet, when trying to avoid losing points, both age groups gambled the same.

In other words, older folks are not risk averse so much as they are just-some-types-of-risk averse.

“Normal human aging affects many cognitive abilities,” wrote Rutledge, lead author, and his colleagues, who suggest dopamine, a neurochemical involved in the brain’s risk-reward system, may explain differences in risk-taking over the lifespan. “A profound change in the aging brain is a gradual decline in the integrity of the dopamine system,” they noted. This loss of dopamine over the lifespan is likely accompanied by a decreasing desire for reward, Rutledge and his colleagues theorize.

The Great Brain Experiment

To understand human gambling instincts, the research team recruited more than 25,000 smartphone users who simply played one of the four games contained within The Great Brain Experiment smartphone app. This particular amusement was all about gambling for points. The participants, who ranged in age from 18 to 69, started with 500 points and then they tried to win as many points as possible in 30 different trials where they chose between a safe option and a risky 50/50 gamble.

During 'gain' trials, players could either choose a guaranteed number of points or a 50/50 chance of winning more points or gaining nothing. During 'loss' trials, the same happened in reverse; players either chose to lose a fixed number of points or gambled on losing no points or more points (than the fixed number). During 'mixed' trials, players could gamble with a chance of gaining or losing points… or choose no points at all.

On average, all age groups chose to gamble in approximately 56 percent of the loss trials and 67 percent of the mixed trials. Looking more closely at these numbers, the researchers discovered 18 to 24 year olds gambled in 72 percent of the gain trials, yet only 64 percent of the 60 to 69 year olds did the same.

This behavioral difference, the researchers say, may be accounted for by dopamine decline which occurs as we age. After all, the older people were not more risk-averse and didn’t make more mistakes than younger people. More likely, they didn’t find the reward very appealing — unlike the younger people — and so they were less willing to take risks to get it.

This experiment does not sufficiently prove reduced dopamine is the reason older people tend to gamble more to avoid losing than to win — more research is needed there. However it does prove apps are one way to go to attract a unique pool of human guinea pigs.

“Smartphone-based data are more representative of the overall population than conventional laboratory experiments,” wrote the researchers, who noted that 73 percent of participants in their study were age 25 or older, while 42 percent reported not having a university degree. By contrast, 85 percent of participants in most other studies are university students.